Where do new Alabamians come from, and where do the former ones go?

An AL.com analysis of Internal Revenue Service statistics gleaned from tax returns in 2011 offers a revealing glimpse of where Alabamians come from, where former ones go and the income that travels with them.

U.S. Census Bureau data has shown for years that Alabama is growing very slowly, but a closer look at IRS data shows the economic impact of migration between Alabama and other states and among counties inside the state.

Much of that modest growth has come from births outnumbering deaths. In 2011 – the most recent years IRS data are available – the state had a net gain of 1,858 people coming from other states and foreign countries. According to the nonpartisan Tax Foundation, Alabama has averaged 108.5 newcomers for every 100 people it has lost since 1992.

"Alabama is one of those states clustered in the middle," said Lyman Stone, an economist with the Washington-based group's Center for State Tax Policy.

While the effect has been modest in Alabama, it has been much more dramatic in some other states. Stone noted that Nevada, for example, has had 140 newcomers for every 100 people who have left, while the state of New York has replaced only 60 people for every 100 who have left.

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The 2011 IRS data offer a one-year snapshot. And it should be noted that since the numbers are tied to tax returns, the statistics do not capture everyone moving in a given year. People who do not file a tax return and their dependents, are left out. Also, the IRS does not report migration trends at the county level in cases in which only a small number of people moved to and from another county.

But clear trends emerge. The data indicate that Alabama enjoyed the biggest net gain from its neighbor to the east. From 2010 to 2011, Alabama received 480 more new residents from Georgia than it lost to the Peach State. Other states where Alabama had a triple-digit net gain were Kentucky (232), Arizona (211) and Arkansas (118).

States where Alabama experienced the biggest net loss of residents tended to be fast-growing states that are pulling newcomers from across the country. Texas led the way, drawing 1,444 more residents from Alabama than it lost. Tennessee (534), Florida (427), Colorado (303), North Carolina (285) and Virginia (224) also grew at Alabama's expense.

Internal migration more dramatic

While migration to and from Alabama might not have a large impact, internal movements – usually rural, shrinking counties to large, growing ones – have had a large and continuing effect, according to experts.

"It's long standing in so many of these places," said Larry Childers, a spokesman for the Alabama Department Economic and Community Affairs. "Barring some new, major industrial developments, it's probably not going to change."

Childers cautioned that while economists can make educated guesses about why people move, precision is impossible.

"People are complex. It's hard to reduce them to a simple formula," he said.

The Alabama counties with the biggest net gain in residents were the same ones that show up at the top of census reports for the fastest-growing areas in Alabama. Baldwin County had the biggest net gain in population, with 2,488 more people moving in than out. Lee (1,996), Madison (1,736), Russell (1,541) and Limestone (1,445) rounded out the top five.

On the flip side, several of the biggest counties had trouble holding on to their residents. Jefferson County saw 2,254 more people leave than arrive. Montgomery County (1,670) and Mobile County (1,495) also had more leave than come.

More than half of Alabama's counties experienced a net loss of people from migration, and an even higher number of counties had an aggregate loss of personal income.

That is because even some counties that had a net increase in population ended up with less personal income because the newcomers has lower incomes than the folks who moved away. Tuscaloosa County, for instance, had a net gain of 527 people from migration but lost $5.6 million in personal income.

The county with the biggest gain in personal income was Baldwin, whose newcomers had $87.1 million more in income than the people who left. Madison was second, with a net gain of $67.3 million.

Outpacing other countries

Stone, the Tax Foundation economist, said the United States historically has seen much greater movement of people within the country and, even after a slowdown since the 1990s, internal migration rates continue to outpace most other countries.

He noted that about 1.5 percent of the U.S. population has moved to a new state within the previous year. While that might sound small, Stone said, that is "quite a few. That's greater than the populations of many states."

It also is greater than the rates in Mexico, Canada and the European Union, Stone said. Even within the European Union, only Denmark has an internal migration rate that exceeds that of the United States, he added.

People moved across state lines with even greater frequency a generation ago. Stone said the 1993 rate, for instance, was about 3 percent. Stone attributed those high rates to frictionless state borders, regional disparity in economic opportunity and a frontier ethos that dates back to the nation's founding.

"That's a huge part of our national narrative," he said.

Stone argued that that high rates of movement have served the country well. It was an important safety valve during the Dust Bowl during 1930s, allowing farmers to head for California and other destinations where work opportunities were better, he said. He added that migration also aided the country's industrialization and the growth of the Sun Belt.

"It's a major reason why the U.S. has been successful," he said.

What is the best migration to have?

So why has state-to-state migration slowed and is that a bad thing?

Stone said those are difficult questions to answer. If the reason is that that there are greater barriers to interstate relocation – teacher certifications not recognized by other states, for instance – then it is a negative, he said.

But Stone said some economists have suggested that reasons for declining rates are the result of less variation in economic opportunity from region to region, relative declines in the cost of air travel and greater ease of interstate road travel. Another possible reason for the decline, he said, is that people have better information about job opportunities. That means that fewer people move to a place and, failing to get a job, move again in less than a year.

"People don't need to move as much," he said.

When looking at migration, people are only half the equation. The income they make matters, too. Alabama, for instance, enjoyed a net gain of more than $22 million income from migration even though more people moved out than in between 2010 and 2011. That is because incomes of the newcomers were a little higher, on average.

But Stone suggested that assessing the desirability of migration is more complicated that adding up income. He said the long-term advantage goes to states that do the best job of attracting entrepreneurs, who may have low incomes when they arrive.

"What really matters is, unfortunately, a piece of data you can't really see and a put a color on a map," he said. "It's the type and quality of migration. ... You want to gain people, really, who are interested in investing in a better life for themselves, their families and their communities."